Roadside Science

Exploring science from the roadside and beyond


1 Comment

The Great Egg Hoax: How a male fish evolved a trick the females can’t resist

A male red zebra cichlid fish displays yellow egg dummies on his back fin. (Photo credit: Maha Dinesh, Creative Commons)

A male red zebra cichlid fish displays orange egg dummies on his back fin. (Photo credit: Maha Dinesh, Creative Commons)

Male stalk-eyed-flies dangle eyes from the ends of long antennae-like stalks. Male widowbirds flaunt tails extending over twice the lengths of their bodies. And male koalas produce deep bellowing calls from highly specialized vocal tracts. There’s no end to the lengths a male animal’s body can be stretched and decorated to win a female’s attention.

But where does the female preference for the elaborate and downright strange come from in the first place?

Mirjam Amcoff, an evolutionary biologist at Uppsala University, suspected that, at least for cichlid fishes, the oddly ornamented males may be tapping into a strong female desire that evolved before it had any connection to choosing a mate. Continue reading